1. Field of the Invention
The present invention relates to a countermeasure system and method for a vehicle passive entry system.
2. Background
It is well known in the automotive industry to provide for remote vehicle access, such as through the use of remote keyless entry (RKE) systems. RKE systems may be characterized as active or passive in nature. In an active system, a switch or pushbutton on a remote transmitter must be activated by an operator in order to have a desired remote function performed, such as locking or unlocking the vehicle doors. In contrast, in a passive RKE system, no such switch or pushbutton activation by an operator is required in order to have a desired remote function performed.
In passive RKE systems, a remote transceiver is provided, which is commonly referred to as a xe2x80x9cfobxe2x80x9d or a xe2x80x9ccard.xe2x80x9d Such a fob or card may be attached to a key chain as a separate unit, or may be part of an ignition key head. The fob or card automatically transmits radio frequency (RF) signals to a vehicle in order to perform any of a variety of remote vehicle functions, such as unlocking a vehicle door, enabling the vehicle engine, and/or activating internal and/or external vehicle lights.
In that regard, passive RKE systems also include a transceiver and/or control unit installed in the vehicle. The vehicle transceiver and/or control unit is provided in communication with various vehicle devices to remotely perform a variety of functions. For example, the vehicle transceiver and/or control unit may be provided in communication with a door lock mechanism in order to unlock a vehicle door in response to an unlock signal received from the remote transceiver, or may be provided in communication with the vehicle engine in order to start the engine in response to an engine start signal received from the remote transceiver.
In that regard, in a passive RKE system, a sensor may be provided in a vehicle door handle for use in providing automatic unlocking of the vehicle door. More particularly, when the vehicle owner makes physical contact with the door handle, such as by grasping or pulling the handle, such a sensor provides the vehicle transceiver and/or control unit with an indication of such contact. After receiving such an indication, the vehicle transceiver and/or control unit automatically transmits a passive entry challenge signal. Upon receipt of that challenge signal, the remote transceiver fob or card carried by the owner determines if the challenge signal is valid and, if so, automatically transmits a vehicle access signal. Upon receipt of the vehicle access signal, the vehicle transceiver and/or control unit, which is provided in communication with the door lock mechanism, generates a control signal for use in unlocking the vehicle door.
In such a fashion, the vehicle owner is remotely and automatically provided with entry to the vehicle, without the need to actuate any switch or button on the fob or card. Of course, if the vehicle transceiver and/or control unit does not receive a vehicle access signal after transmitting the challenge signal, such as when the door handle is grasped by an individual without an authorized fob or card, the vehicle door remains locked. Similarly, if a fob or card carried by the vehicle owner determines that a received challenge signal is not valid, such as where the owner mistakenly attempts to enter another vehicle, no vehicle access signal is transmitted by the fob or card.
However, it is also known in the automotive industry that various relay attack methods and devices may be employed to gain unauthorized entry to a vehicle equipped with such a passive RKE system. Thus, in a vehicle passive entry system, there exists a need for a countermeasure system and method for deterring such unauthorized entry and vehicle theft.
Accordingly, the present invention provides a countermeasure system and method for use in a passive entry system for a vehicle.
According to one embodiment of the present invention, in a passive entry system for a vehicle having a door lock mechanism and an engine, a countermeasure system is provided. The countermeasure system comprises a passive entry control module for mounting in the vehicle, the control module comprising a transceiver for transmitting a passive entry challenge signal and for receiving a vehicle access signal. The countermeasure system further comprises a remote unit for receiving the passive entry challenge signal, determining if the passive entry challenge signal is valid, and transmitting a vehicle access signal for use in actuating the door look mechanism to permit access to the vehicle if the passive entry challenge signal is determined valid. The remote unit comprises an indicator for use in generating an alert if the passive entry challenge signal is determined valid, and a switch for use in manually disabling transmission of the vehicle access signal.
According to another embodiment of the present invention, in a passive entry system for a vehicle having a door lock mechanism and an engine, a countermeasure method is provided. The countermeasure method comprises providing a remote unit for receiving a passive entry challenge signal, determining if the passive entry challenge signal is valid, and transmitting a vehicle access signal for use in actuating the door look mechanism to permit access to the vehicle if the passive entry challenge signal is determined valid. The remote unit comprises an indicator for use in generating an alert if the passive entry challenge signal is determined valid, and a switch for use in manually disabling transmission of the vehicle access signal.
The following detailed description and accompanying drawings set forth preferred embodiments of the present invention.